下颌第一恒磨牙四根管检出率及解剖形态的锥形束CT检查  

Cone-beam computed tomography study of anatomy of permanent mandibular first molars with four root canals and its relevance ratio

作　　者：孙银珑[1] 楚金普[1] 闫波[1] 徐力[1] 姜文辉[1] 

机构地区：[1]郑州大学口腔医学院,郑州450052

出　　处：《郑州大学学报（医学版）》2014年第4期559-562,共4页Journal of Zhengzhou University(Medical Sciences)

摘　　要：目的:利用锥形束CT(CBCT)研究下颌第一恒磨牙四根管在人群中的发生率以及根管系统和髓室底的解剖特点。方法:利用按照纳入标准取得的180例患者的CBCT图像资料,观察下颌第一恒磨牙四根管的发生率(包括个体发生率、牙齿发生率)及左右对称率。然后筛选出具有四根管的下颌第一恒磨牙,根据牙根数目不同分为三根型组和两根型组,每组随机抽取25例样本,利用Kodak Dental 6.12.10软件对图像进行重建,对两组的根管系统进行分型,观察根管口水平的髓室横断面,测量2组根管口水平近颊至近舌、近颊至远颊、远舌至远颊、远舌至近舌根管口的距离。结果:下颌第一恒磨牙四根管的牙齿发生率和个体发生率分别为45.1%(119/264牙)和43.3%(78/180人)。男性组左右相关系数为0.635,女性组为0.574。近中根以2-2-2型根管为主,在三根型组发生率为68.0%(17/25),两根型组为76.0%(19/25);1-1-1型根管常见于三根型的远颊根、远舌根,发生率均为100.0%(25/25)。两根型下颌第一恒磨牙的远中根比较常见的为2-2-2型和2-2-1型,发生率依次是32.0%(8/25)、28.0%(7/25)。远颊与远舌根管口的间距差异有统计学意义(t=8.569,P<0.001)。结论:CBCT成像可以反映下颌第一恒磨牙四根管的解剖形态,为下颌第一恒磨牙的根管治疗提供了准确的影像学参考。Aim： To detect the prevalence of four root canals in permanent mandibular first molars and investigate the pulp floor and root canal system in mandibular first molars with four root canals by using cone-beam computed tomography（ CBCT）. Methods： A total of 180 Chinese patients＇ CBCT images were examined. The four root canals＇ incidences and bilateral concurrence rates were determined for the permanent mandibular first molars. The mandibular first molars with four root canals according to the difference of root number are divided into two groups： group A was three-rooted and group B was two-rooted,each group had 25 randomly selected samples. The images of two groups were analyzed by Kodak Dental6. 12. 10,the root canal morphology was analyzed and the pulp chamber＇ s cross-sectional morphology was observed. Results： The prevalence of four root canals in the mandibular first molars was 43. 3%（ 78 /180） calculated by individuals,and 45. 1%（ 119 /264） calculated by teeth. The correlation coefficient was 0. 635 in the male group and was 0. 574 in the femal group. The mesial root predominately contained a type 2-2-2 root canal,with a frequency of 68. 0%（ 17 /25） in the three-rooted molar group and 76. 0%（ 19 /25） in the two-rooted molar group. Type 1-1-1 canals were seen more frequently in the DL and DB roots of the three-rooted first molars,and the incidences were all 100. 0%（ 25 /25）. The mean interorifice distances from DL canal to DB which was statistical significance were（ 3. 81 ± 0. 55） and（ 2. 03 ± 0. 88） mm,respectively（ t =8.569,P〈0. 001）. Conclusion： CBCT has high accuracy for observing the anatomy of the root canal and can be used to study the morphology of the mandibular first molars as important tools and provide a favorable reference for the clinical work.

关 键 词：锥形束CT 下颌第一恒磨牙 根管解剖形态 

分 类 号：R781.33[医药卫生—口腔医学]